Printing cylinder



P. L. MILLER CYLINDER PRINTING w m R w a J m N T I/ A M R m I May 13, 1941. P. L. MILLER PRINTING CYLINDER 2 Sheets-Sheet 2 Filed Jan. 29, 1941 A. k 4 g g M :NVENTOR Pay] lee /I////e2 4/ ATTO lqIi Patented May 13, 1941 PRINTING CYLINDER Paul Lee Miller, Clearwater, S. 0., assignor to United Merchants & Manufacturers, Inc., New York, N. Y., a corporation of Delaware Application January 29, 1941, Serial No. 376,419-

8 Claims.

This invention relates to improvements in printing cylinders of the type used in conjunction with engraved cylindrical rolls such, for example, as are used in a textile printing machine, and its object is to provide a cylinder with an adjustable crown and a simple mechanism for making the desired adjustment.

To secure a clear sharp print of fine patterns or lines, heavy pressure must be exerted against the web or sheet passing between a roll and the cylinder. The bearings of the printing rolls or of the cylinder are made adjustable so that they may be moved toward each other to provide the required pressure. This pressure tends to bend the rolls so that the pressure is less at the central part of the web between them than it is at the parts near its ends. To counteract this inequality of pressure it is common practice to lap the cylinder by winding a web of textile material, such as a woolen sheet, around it to increase the efiective diameter of the central part of the cylinder. This has the disadvantage of leaving marks on the printed web at the ends or the edges of the lapping. The cylinders are sometimes provided with a crowned coating of elastic material, such as rubber, as shown in Patent No. 2,111,613, issued to United Merchants 8; Manufacturers, Inc., as assignee of Murray N. Bulford, March 22, 1938. This meets the requirements for any given printing roll and any given pressure, but is not suitable for different rolls and different pressures.

It is the object of this invention to provide a cylinder which can be used effectively with different rolls and. under different pressure conditions. In the following specification I will point out some embodiments of my invention, the'novel features of which will be pointed out in appended claims.

Referring to the drawings,

Fig. 1 is a sectional side elevation of a cylinder which is made according to and embodies my invention;

Fig. 2 is a sectional end elevation of the parts shown in Fig. 1, the section being taken on the line 22 of the latter figure;

Fig. 3 is a sectional end elevation on an enlarged scale of some of the parts shown in Fig. 2;

Fig. 4 is a plan view of a part of the device shown in Fig. 1, with its outer cover removed;

Fig. 5 illustrates an adjusting mechanism in side elevation, with some of the parts broken away;

Fig. 6 is a sectional side elevation of another form of adjusting mechanism;

Fig. '7 is a sectional end elevation of the parts shown in Fig. 6.

A further modification of mechanism for effecting the desired adjustment is shown in side elevation in Fig. 8 and in end view in Fig. 9.

Referring first to Figs. 1-4 inclusive, l0 designates a shaft upon which the cylinder is mounted. H are spaced spiders affixed to the shaft and to a cylinder 20 near the ends of the latter. The central part of the shaft is provided with a thread of fine pitch, as shown at l2, to support an expanding member l3 which has an outer tapered or conical surface and a lock nut l4, both of which are in threaded engagement with the shaft and. both of which are provided with spanner wrench holes. I5 is a housing afiixed to the shaft. This is recessed to clear the expanding member and is provided with a plurality of radially disposed grooves for holding and guiding rigid rods Hi, the inner ends of which are adapted to abut the outer surface of the expanding member l3. l! is a plate affixed tohousing l5 to retain the rods IS in the guides. On the outer end of each of the rods I6 is a segmental member l8. The ends of these members abut when the cylinder 20 is, not expanded and together form a band. at the center of the cylinder.

The part of the cylinder between the spiders H, II is slit longitudinally, as at 2|, to form a plurality of narrow axially disposed bars 22. 23 is an outer cover of elastic material, such as rubber, surrounding the cylinder 20.

It is obvious that if the expanding member I3 is turned in such a direction as to cause it to move to the left, as viewed in Fig. 1, it will push the rods outwardly, and that the segmental members I8 will have a similar effect upon the central portions of the bars 22 causing the bars to flex and to form the desired crown on the periphery of the cylinder. The increase in the diameter of the central portion of the cylinder is extremely small, a maximum increment of three-hundredths of an inch being suflicient to meet most requirements. This is not enough to cause any noticeable decrease in the distance between the spiders or in the width of the slits 2|. The outer covering 23 spans the slits anyway and forms a circumferentially continuous resilient backing for the web to be printed.

A mechanism for rotating the expanding member I3 on the shaft I0 is shown in Fig. 5. In this case a collar 30 which is afiixed to the shaft forms a bearing 3| for a longitudinally disposed shaft 32. A bevel pinion 33 is affixed to an end of this shaft and. an operating handle 34 is affixed to its other end. 35 is a bevel gear affixed to or formed on the expanding member.

If it is desired to impart a radial movement to the rods 5 positively in both directions, the arrangement shown in Figs. 6 and '7 may be used. in this case an expanding member 40 is slidably mounted on the shaft Ill and is held against relative rotation thereon by a spline ll. This expanding member is provided with inclined undercut grooves 42 and which receive the inner ends of the rods lfiA which are shaped to fit them. Longitudinal movement is imparted to the expanding member by a collar 43 mounted on the shaft In in engagement with the threads IZA on the shaft. This collar has a portion overlapping an end of the expansion member and projections 44 which fit an annular groove E5 in the expanding member,

Another mechanism for expanding the cylinder is shown in Figs. 8 and 9. The underside of the bars 22A is thickened, as at 59, at the central part of the cylinder. 5|, 5| are longitudinally movable circular plates which are bored to fit the shaft I0. The outer peripheries of these plates fit the inner surface of the bars 22A when the plates are longitudinally separated, as shown in Fig. 8.

52 designates longitudinal shafts mounted in angularly spaced relation in some of the spokes of the spiders H and held against longitudinal movement thereby. The central portions of the shafts 52 are provided with right and left hand screw threads 53 and engage internal thread-s in the plates 51. On one end of each of the shafts 52 is affixed a gear 54. These mesh with a gear 55 mounted on shaft II).

By rotating gear 55 the plates 5| are moved toward or away from each other. As they approach each other the thickened portion 50 of the bars 22A ride up on them to expand the cylinder. This thickened portion is beveled in opposite directions to make this expansion gradual.

Several mechanisms for accomplishing the desired result have been illustrated and described to show that the invention is not limited to any specific arrangement and I intend no limitations other than those imposed by the appended claims.

What I claim is:

1. A press cylinder having a hollow flexible body and adjustable means for bending outwardly the part of said body intermediate its ends.

2. A press cylinder having a hollow flexible body, a shaft for supporting the body, a tapered expanding member on said shaft, radially disposed arms extending from said member to the inner surface of the body near the center of the body, and means for adjusting the longitudinal position of the expanding member on the shaft.

3. A press cylinder having a hollow flexible body, a shaft for supporting the body, said shaft having a threaded portion intermediate the ends of said body, an internally threaded tapered expanding member on the threaded portion of the shaft, radially disposed arms extending from said member to the inner surface of the body, and means for rotating the member on the shaft to adjust its longitudinal position on the shaft.

4. A press cylinder having a hollow flexible body, a shaft for supporting the body, a tapered expanding member on said shaft, radially disposed arms extending from said member to the inner surface of the body near the center of the body, enlarged members on the outer ends of said arms together forming an interrupted annular ring, and means for adjusting the longitudinal position of the expanding member on the shaft.

5. A press cylinder having a hollow body slitted to form a plurality of flexible longitudinal bars, a shaft for supporting the body, a tapered expanding member on said shaft, radially disposed arms extending from said member to the inner surface of the body near the center of the body, enlarged members on the outer ends of said arms together forming an interrupted annular ring, and means for adjusting the longitudinal position of the expanding member on the shaft.

6. A press cylinder having a hollow body slitted to form: a plurality of flexible longitudinal bars, a shaft for supporting the body, a tapered expanding member on said shaft, radially disposed arms extending from said member to the inner surface of the body near the center of the body, enlarged members on the outer ends of said arms together forming an interrupted annular ring, and means for adjusting the longitudinal position of the expanding member on the shaft and a cover of resilient material over the body.

7. A press cylinder having a hollow body slitted to form a plurality of flexible longitudinal bars, an inwardly projecting tapered enlargement near the center of each bar, a shaft for supporting the body, a pair of disks surrounding the shaft and arranged to engage said projections, and means for moving said disks toward and away from each other.

8. A press cylinder having a hollow body slitted to form a plurality of flexible longitudinal bars, an inwardly projecting tapered enlargement near the center of each bar, a main shaft for supporting the body, a pair of disks surrounding the shaft and arranged to engage said projections, a plurality of angularly spaced auxiliary shafts parallel with the main shaft passing through said disks, right and left hand threads on the auxiliary shafts engaging the disks, and means for rotating the auxiliary shafts simultaneously.

PAUL LEE MILLER. 

